When health failed him, he retired to Monte Pulciano, where from 1607 to 1611 he acted as bishop. In 1610 he published his De Potestate summiPontificis in rebus temporalibus directed against the posthumous work of William Barclay of Aberdeen, which denied the temporal power of the pope.
That which is best known and has been most frequently edited is the Hotµavfipl)s sive De potestate et sapientia divina (Hotµavfipljs being the Divine Intelligence, 7roeµ)v avfip&v),‘ which consists of fifteen chapters treating of such subjects as the nature of God, the origin of the world, the creation and fall of man, and the divine illumination which is the sole means of his deliverance.
Bodin defines the state thus: "Respublica est familiarum rerumque inter ipsas communium, summa potestate ac ratione moderata multitudo."
It is entitled Vindiciae contra tyrannos, sive de principis in populum populique in principem legitima potestate, Stephano Junio Bruto Celta auctore, and is thought to have been published at Basel (1579) although it bears the imprint of, Edinburgh.
For his work in connexion with gunpowder, the invention of which has been claimed for him on the ground of a passage in his De mirabili potestate antis et naturae, see Gunpowder.